# "UserWarning: Matplotlib is building the font cache using fc-list." never resolves

Hi,

I just downloaded and installed Sage 9.0 on windows. Typing the following:

```
plot(x^3, (x,0,5))
```

Gives the following error:

```
/opt/sagemath-9.0/local/lib/python3.7/site-packages/matplotlib/font_manager.py:281: UserWarning: Matplotlib is building the font cache using fc-list. This may take a moment.
'Matplotlib is building the font cache using fc-list. '
```

The kernel is running and nothing happens, even after waiting for a long time.

I did some googling. This stackexchange answer suggesting using

```
import matplotlib as mpl
print mpl.get_cachedir()
```

To get the directory of matplotlib, in order to (as suggested here) delete these files:

```
fontList.cache
fontList.py3k.cache
tex.cache
```

I did this, the folder I got was: /home/sage/.sage/matplotlib-1.5.1

But this folder is empty (according to the Sage shell). There are no files to delete there.

Any suggestions for how to get plot to work?

Thanks.

I downgraded to Sage 8.8 and now the plot command works as expected.

I experienced the same problem. I first tried to upgrade matplotlib by launching the sagemath shell running

`pip install --upgrade matplotlib`

. Then I use the following command to try the plotting function`P = matrix_plot(matrix(2,[1,1,3,3]))`

and then`P`

. If for the first time the console hangs at the message "Matplotlib is building the font cache using fc-list.", then press ctrl+c to break it and try the plot function again. Since I cannot replicate the problem now I am not sure if this is the solution to the problem. Good luck.